1 /******************************************************************************
3 * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
44 #include <acpi/acpi.h>
45 #include <acpi/acparser.h>
46 #include <acpi/amlcode.h>
47 #include <acpi/acdispat.h>
48 #include <acpi/acinterp.h>
49 #include <acpi/acnamesp.h>
50 #include <acpi/acdisasm.h>
52 #define _COMPONENT ACPI_DISPATCHER
53 ACPI_MODULE_NAME("dsmethod")
55 /*******************************************************************************
57 * FUNCTION: acpi_ds_method_error
59 * PARAMETERS: Status - Execution status
60 * walk_state - Current state
64 * DESCRIPTION: Called on method error. Invoke the global exception handler if
65 * present, dump the method data if the disassembler is configured
67 * Note: Allows the exception handler to change the status code
69 ******************************************************************************/
71 acpi_ds_method_error(acpi_status status
, struct acpi_walk_state
*walk_state
)
73 ACPI_FUNCTION_ENTRY();
75 /* Ignore AE_OK and control exception codes */
77 if (ACPI_SUCCESS(status
) || (status
& AE_CODE_CONTROL
)) {
81 /* Invoke the global exception handler */
83 if (acpi_gbl_exception_handler
) {
85 /* Exit the interpreter, allow handler to execute methods */
87 acpi_ex_exit_interpreter();
90 * Handler can map the exception code to anything it wants, including
91 * AE_OK, in which case the executing method will not be aborted.
93 status
= acpi_gbl_exception_handler(status
,
94 walk_state
->method_node
?
95 walk_state
->method_node
->
98 walk_state
->aml_offset
,
100 (void)acpi_ex_enter_interpreter();
102 #ifdef ACPI_DISASSEMBLER
103 if (ACPI_FAILURE(status
)) {
105 /* Display method locals/args if disassembler is present */
107 acpi_dm_dump_method_info(status
, walk_state
, walk_state
->op
);
114 /*******************************************************************************
116 * FUNCTION: acpi_ds_begin_method_execution
118 * PARAMETERS: method_node - Node of the method
119 * obj_desc - The method object
120 * calling_method_node - Caller of this method (if non-null)
124 * DESCRIPTION: Prepare a method for execution. Parses the method if necessary,
125 * increments the thread count, and waits at the method semaphore
126 * for clearance to execute.
128 ******************************************************************************/
131 acpi_ds_begin_method_execution(struct acpi_namespace_node
* method_node
,
132 union acpi_operand_object
* obj_desc
,
133 struct acpi_namespace_node
* calling_method_node
)
135 acpi_status status
= AE_OK
;
137 ACPI_FUNCTION_TRACE_PTR("ds_begin_method_execution", method_node
);
140 return_ACPI_STATUS(AE_NULL_ENTRY
);
143 /* Prevent wraparound of thread count */
145 if (obj_desc
->method
.thread_count
== ACPI_UINT8_MAX
) {
147 "Method reached maximum reentrancy limit (255)"));
148 return_ACPI_STATUS(AE_AML_METHOD_LIMIT
);
152 * If there is a concurrency limit on this method, we need to
153 * obtain a unit from the method semaphore.
155 if (obj_desc
->method
.semaphore
) {
157 * Allow recursive method calls, up to the reentrancy/concurrency
158 * limit imposed by the SERIALIZED rule and the sync_level method
161 * The point of this code is to avoid permanently blocking a
162 * thread that is making recursive method calls.
164 if (method_node
== calling_method_node
) {
165 if (obj_desc
->method
.thread_count
>=
166 obj_desc
->method
.concurrency
) {
167 return_ACPI_STATUS(AE_AML_METHOD_LIMIT
);
172 * Get a unit from the method semaphore. This releases the
173 * interpreter if we block
176 acpi_ex_system_wait_semaphore(obj_desc
->method
.semaphore
,
181 * Allocate an Owner ID for this method, only if this is the first thread
182 * to begin concurrent execution. We only need one owner_id, even if the
183 * method is invoked recursively.
185 if (!obj_desc
->method
.owner_id
) {
186 status
= acpi_ut_allocate_owner_id(&obj_desc
->method
.owner_id
);
187 if (ACPI_FAILURE(status
)) {
188 return_ACPI_STATUS(status
);
193 * Increment the method parse tree thread count since it has been
194 * reentered one more time (even if it is the same thread)
196 obj_desc
->method
.thread_count
++;
197 return_ACPI_STATUS(status
);
200 /*******************************************************************************
202 * FUNCTION: acpi_ds_call_control_method
204 * PARAMETERS: Thread - Info for this thread
205 * this_walk_state - Current walk state
206 * Op - Current Op to be walked
210 * DESCRIPTION: Transfer execution to a called control method
212 ******************************************************************************/
215 acpi_ds_call_control_method(struct acpi_thread_state
*thread
,
216 struct acpi_walk_state
*this_walk_state
,
217 union acpi_parse_object
*op
)
220 struct acpi_namespace_node
*method_node
;
221 struct acpi_walk_state
*next_walk_state
= NULL
;
222 union acpi_operand_object
*obj_desc
;
223 struct acpi_parameter_info info
;
226 ACPI_FUNCTION_TRACE_PTR("ds_call_control_method", this_walk_state
);
228 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH
,
229 "Execute method %p, currentstate=%p\n",
230 this_walk_state
->prev_op
, this_walk_state
));
233 * Get the namespace entry for the control method we are about to call
235 method_node
= this_walk_state
->method_call_node
;
237 return_ACPI_STATUS(AE_NULL_ENTRY
);
240 obj_desc
= acpi_ns_get_attached_object(method_node
);
242 return_ACPI_STATUS(AE_NULL_OBJECT
);
245 /* Init for new method, wait on concurrency semaphore */
247 status
= acpi_ds_begin_method_execution(method_node
, obj_desc
,
248 this_walk_state
->method_node
);
249 if (ACPI_FAILURE(status
)) {
253 if (!(obj_desc
->method
.method_flags
& AML_METHOD_INTERNAL_ONLY
)) {
255 /* 1) Parse: Create a new walk state for the preempting walk */
258 acpi_ds_create_walk_state(obj_desc
->method
.owner_id
, op
,
260 if (!next_walk_state
) {
261 return_ACPI_STATUS(AE_NO_MEMORY
);
264 /* Create and init a Root Node */
266 op
= acpi_ps_create_scope_op();
268 status
= AE_NO_MEMORY
;
272 status
= acpi_ds_init_aml_walk(next_walk_state
, op
, method_node
,
273 obj_desc
->method
.aml_start
,
274 obj_desc
->method
.aml_length
,
276 if (ACPI_FAILURE(status
)) {
277 acpi_ds_delete_walk_state(next_walk_state
);
281 /* Begin AML parse */
283 status
= acpi_ps_parse_aml(next_walk_state
);
284 acpi_ps_delete_parse_tree(op
);
287 /* 2) Execute: Create a new state for the preempting walk */
289 next_walk_state
= acpi_ds_create_walk_state(obj_desc
->method
.owner_id
,
290 NULL
, obj_desc
, thread
);
291 if (!next_walk_state
) {
292 status
= AE_NO_MEMORY
;
296 * The resolved arguments were put on the previous walk state's operand
297 * stack. Operands on the previous walk state stack always
298 * start at index 0. Also, null terminate the list of arguments
300 this_walk_state
->operands
[this_walk_state
->num_operands
] = NULL
;
302 info
.parameters
= &this_walk_state
->operands
[0];
303 info
.parameter_type
= ACPI_PARAM_ARGS
;
305 status
= acpi_ds_init_aml_walk(next_walk_state
, NULL
, method_node
,
306 obj_desc
->method
.aml_start
,
307 obj_desc
->method
.aml_length
, &info
, 3);
308 if (ACPI_FAILURE(status
)) {
313 * Delete the operands on the previous walkstate operand stack
314 * (they were copied to new objects)
316 for (i
= 0; i
< obj_desc
->method
.param_count
; i
++) {
317 acpi_ut_remove_reference(this_walk_state
->operands
[i
]);
318 this_walk_state
->operands
[i
] = NULL
;
321 /* Clear the operand stack */
323 this_walk_state
->num_operands
= 0;
325 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH
,
326 "Starting nested execution, newstate=%p\n",
329 if (obj_desc
->method
.method_flags
& AML_METHOD_INTERNAL_ONLY
) {
330 status
= obj_desc
->method
.implementation(next_walk_state
);
333 return_ACPI_STATUS(status
);
336 /* Decrement the thread count on the method parse tree */
338 if (next_walk_state
&& (next_walk_state
->method_desc
)) {
339 next_walk_state
->method_desc
->method
.thread_count
--;
342 /* On error, we must delete the new walk state */
344 acpi_ds_terminate_control_method(next_walk_state
);
345 acpi_ds_delete_walk_state(next_walk_state
);
346 return_ACPI_STATUS(status
);
349 /*******************************************************************************
351 * FUNCTION: acpi_ds_restart_control_method
353 * PARAMETERS: walk_state - State for preempted method (caller)
354 * return_desc - Return value from the called method
358 * DESCRIPTION: Restart a method that was preempted by another (nested) method
359 * invocation. Handle the return value (if any) from the callee.
361 ******************************************************************************/
364 acpi_ds_restart_control_method(struct acpi_walk_state
*walk_state
,
365 union acpi_operand_object
*return_desc
)
369 ACPI_FUNCTION_TRACE_PTR("ds_restart_control_method", walk_state
);
371 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH
,
372 "****Restart [%4.4s] Op %p return_value_from_callee %p\n",
373 (char *)&walk_state
->method_node
->name
,
374 walk_state
->method_call_op
, return_desc
));
376 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH
,
377 " return_from_this_method_used?=%X res_stack %p Walk %p\n",
378 walk_state
->return_used
,
379 walk_state
->results
, walk_state
));
381 /* Did the called method return a value? */
385 /* Are we actually going to use the return value? */
387 if (walk_state
->return_used
) {
389 /* Save the return value from the previous method */
391 status
= acpi_ds_result_push(return_desc
, walk_state
);
392 if (ACPI_FAILURE(status
)) {
393 acpi_ut_remove_reference(return_desc
);
394 return_ACPI_STATUS(status
);
398 * Save as THIS method's return value in case it is returned
399 * immediately to yet another method
401 walk_state
->return_desc
= return_desc
;
405 * The following code is the
406 * optional support for a so-called "implicit return". Some AML code
407 * assumes that the last value of the method is "implicitly" returned
408 * to the caller. Just save the last result as the return value.
409 * NOTE: this is optional because the ASL language does not actually
410 * support this behavior.
412 else if (!acpi_ds_do_implicit_return
413 (return_desc
, walk_state
, FALSE
)) {
415 * Delete the return value if it will not be used by the
418 acpi_ut_remove_reference(return_desc
);
422 return_ACPI_STATUS(AE_OK
);
425 /*******************************************************************************
427 * FUNCTION: acpi_ds_terminate_control_method
429 * PARAMETERS: walk_state - State of the method
433 * DESCRIPTION: Terminate a control method. Delete everything that the method
434 * created, delete all locals and arguments, and delete the parse
437 ******************************************************************************/
439 void acpi_ds_terminate_control_method(struct acpi_walk_state
*walk_state
)
441 union acpi_operand_object
*obj_desc
;
442 struct acpi_namespace_node
*method_node
;
445 ACPI_FUNCTION_TRACE_PTR("ds_terminate_control_method", walk_state
);
451 /* The current method object was saved in the walk state */
453 obj_desc
= walk_state
->method_desc
;
458 /* Delete all arguments and locals */
460 acpi_ds_method_data_delete_all(walk_state
);
463 * Lock the parser while we terminate this method.
464 * If this is the last thread executing the method,
465 * we have additional cleanup to perform
467 status
= acpi_ut_acquire_mutex(ACPI_MTX_PARSER
);
468 if (ACPI_FAILURE(status
)) {
472 /* Signal completion of the execution of this method if necessary */
474 if (walk_state
->method_desc
->method
.semaphore
) {
476 acpi_os_signal_semaphore(walk_state
->method_desc
->method
.
478 if (ACPI_FAILURE(status
)) {
480 "Could not signal method semaphore"));
482 /* Ignore error and continue cleanup */
487 * There are no more threads executing this method. Perform
488 * additional cleanup.
490 * The method Node is stored in the walk state
492 method_node
= walk_state
->method_node
;
494 /* Lock namespace for possible update */
496 status
= acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE
);
497 if (ACPI_FAILURE(status
)) {
502 * Delete any namespace entries created immediately underneath
505 if (method_node
&& method_node
->child
) {
506 acpi_ns_delete_namespace_subtree(method_node
);
510 * Delete any namespace entries created anywhere else within
511 * the namespace by the execution of this method
513 acpi_ns_delete_namespace_by_owner(walk_state
->method_desc
->method
.
515 status
= acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
517 /* Are there any other threads currently executing this method? */
519 if (walk_state
->method_desc
->method
.thread_count
) {
521 * Additional threads. Do not release the owner_id in this case,
522 * we immediately reuse it for the next thread executing this method
524 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH
,
525 "*** Completed execution of one thread, %d threads remaining\n",
526 walk_state
->method_desc
->method
.
529 /* This is the only executing thread for this method */
532 * Support to dynamically change a method from not_serialized to
533 * Serialized if it appears that the method is incorrectly written and
534 * does not support multiple thread execution. The best example of this
535 * is if such a method creates namespace objects and blocks. A second
536 * thread will fail with an AE_ALREADY_EXISTS exception
538 * This code is here because we must wait until the last thread exits
539 * before creating the synchronization semaphore.
541 if ((walk_state
->method_desc
->method
.concurrency
== 1) &&
542 (!walk_state
->method_desc
->method
.semaphore
)) {
543 status
= acpi_os_create_semaphore(1, 1,
549 /* No more threads, we can free the owner_id */
551 acpi_ut_release_owner_id(&walk_state
->method_desc
->method
.
556 (void)acpi_ut_release_mutex(ACPI_MTX_PARSER
);
560 #ifdef ACPI_INIT_PARSE_METHODS
562 * Note 11/2005: Removed this code to parse all methods during table
563 * load because it causes problems if there are any errors during the
564 * parse. Also, it seems like overkill and we probably don't want to
565 * abort a table load because of an issue with a single method.
568 /*******************************************************************************
570 * FUNCTION: acpi_ds_parse_method
572 * PARAMETERS: Node - Method node
576 * DESCRIPTION: Parse the AML that is associated with the method.
578 * MUTEX: Assumes parser is locked
580 ******************************************************************************/
582 acpi_status
acpi_ds_parse_method(struct acpi_namespace_node
*node
)
585 union acpi_operand_object
*obj_desc
;
586 union acpi_parse_object
*op
;
587 struct acpi_walk_state
*walk_state
;
589 ACPI_FUNCTION_TRACE_PTR("ds_parse_method", node
);
591 /* Parameter Validation */
594 return_ACPI_STATUS(AE_NULL_ENTRY
);
597 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
,
598 "**** Parsing [%4.4s] **** named_obj=%p\n",
599 acpi_ut_get_node_name(node
), node
));
601 /* Extract the method object from the method Node */
603 obj_desc
= acpi_ns_get_attached_object(node
);
605 return_ACPI_STATUS(AE_NULL_OBJECT
);
608 /* Create a mutex for the method if there is a concurrency limit */
610 if ((obj_desc
->method
.concurrency
!= ACPI_INFINITE_CONCURRENCY
) &&
611 (!obj_desc
->method
.semaphore
)) {
612 status
= acpi_os_create_semaphore(obj_desc
->method
.concurrency
,
613 obj_desc
->method
.concurrency
,
614 &obj_desc
->method
.semaphore
);
615 if (ACPI_FAILURE(status
)) {
616 return_ACPI_STATUS(status
);
621 * Allocate a new parser op to be the root of the parsed
624 op
= acpi_ps_alloc_op(AML_METHOD_OP
);
626 return_ACPI_STATUS(AE_NO_MEMORY
);
629 /* Init new op with the method name and pointer back to the Node */
631 acpi_ps_set_name(op
, node
->name
.integer
);
632 op
->common
.node
= node
;
635 * Get a new owner_id for objects created by this method. Namespace
636 * objects (such as Operation Regions) can be created during the
639 status
= acpi_ut_allocate_owner_id(&obj_desc
->method
.owner_id
);
640 if (ACPI_FAILURE(status
)) {
644 /* Create and initialize a new walk state */
647 acpi_ds_create_walk_state(obj_desc
->method
.owner_id
, NULL
, NULL
,
650 status
= AE_NO_MEMORY
;
654 status
= acpi_ds_init_aml_walk(walk_state
, op
, node
,
655 obj_desc
->method
.aml_start
,
656 obj_desc
->method
.aml_length
, NULL
, 1);
657 if (ACPI_FAILURE(status
)) {
658 acpi_ds_delete_walk_state(walk_state
);
663 * Parse the method, first pass
665 * The first pass load is where newly declared named objects are added into
666 * the namespace. Actual evaluation of the named objects (what would be
667 * called a "second pass") happens during the actual execution of the
668 * method so that operands to the named objects can take on dynamic
671 status
= acpi_ps_parse_aml(walk_state
);
672 if (ACPI_FAILURE(status
)) {
676 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
,
677 "**** [%4.4s] Parsed **** named_obj=%p Op=%p\n",
678 acpi_ut_get_node_name(node
), node
, op
));
681 * Delete the parse tree. We simply re-parse the method for every
682 * execution since there isn't much overhead (compared to keeping lots
683 * of parse trees around)
685 acpi_ns_delete_namespace_subtree(node
);
686 acpi_ns_delete_namespace_by_owner(obj_desc
->method
.owner_id
);
689 acpi_ut_release_owner_id(&obj_desc
->method
.owner_id
);
692 acpi_ps_delete_parse_tree(op
);
693 return_ACPI_STATUS(status
);